RESUMEN
Objective: The aim of this study was the comparison of the functional stability of dominant and non-dominant shoulder in female volleyball players with and without anterior shoulder instability, using YBT-UQ
Materials and Methods: In this descriptive study, 28 female university volleyball players [age=20 to 25 years] were categorized into healthy [n=14] and anterior shoulder instability [n=14] group. Upper quarter y balance test [YBT-UQ] was used for measuring functional stability of both dominant and non-dominant shoulder. After checking the normal distribution of the results with 1-s Kolmogorov-Smirnov, paired sample t-test and independent sample t-test were used for comparing the dominant and non-dominant shoulder's functional stability and for comparing the results between groups, respectively
Results: Higher YBT-UQ composite score was observed in non-dominant shoulder and dominant shoulder of the healthy group and the non-dominant shoulder and dominant [injured] shoulder of shoulder instability group, respectively. No significant difference was observed between functional stability of both shoulders of the healthy group [P=0.144], while the functional stability of the non-dominant shoulders of the instability group was significantly higher than the dominant unstable shoulders [P=0.001]. The results of functional stability of the unstable shoulders of the injured group were significantly lower than the results of the dominant shoulders of the healthy group, while in non-dominant side, all directions but the Superolateral direction showed significant difference
Conclusion: Based on the results of this study, functional stability of the unstable shoulder of female university volleyball players is lower than the functional stability of their non-dominant side or the functional stability of the healthy subjects; Therefore, we suggest that the upper extremity stabilization exercises, specially the closed kinetic chain exercises should be added to the shoulder rehabilitation programs